1. Field of the Invention
The present invention is directed to rodenticide compositions. Specifically, the invention includes a mixture of an anticoagulant, a bait, and a laceration means.
2. Description of the Prior Art
The rodent problem has been recognized worldwide as a serious and age-old problem. In some underdeveloped areas of the world, rodents actively compete with man for available food supplies. In the more developed countries, rodents still manage to invade food warehouses, packing plants, slaughterhouses, food stores, farms, and fruit groves to cause substantial economic losses. When sufficiently hungry, and lacking other sources of food, they will in some cases, attack humans. They have also been known historically to be the carriers of a variety of diseases. Considering the magnitude and persistance of the problem, significant time and effort has been focused on numerous means and methods of resolving it.
Until the discovery of effective anticoagulants, most notable being warfarin, 3-(.alpha.-acetonlybenzyl) 4-hydroxycoumarin, numerous toxic methods have been employed. Such substances as arsenic, toxic and rapidly acting, single dose, stomach poisons such as strychnine or sodium fluoracetate have found widespread use. The use of these highly toxic materials has had significant drawbacks, however, since being so toxic, they provide a serious potential for accidental poisoning of humans, particularly children and domestic animals. Likewise, in the hands of non-professionals, some of these substances can be quite hazardous to those individuals dispensing the materials.
Studies have also indicated that some of the rapidly acting poisons frequently are rejected by a majority of the rodent colony. Such a response, known as "bait shyness", develops after toxic manifestations in several of the rodents are observed by the remaining rodents.
The introduction of anticoagulants, such as warfarin, into the rodenticide field, initiated a new and effective concept of multiple dose bait. When warfarin, or its sodium or potassium derivatives, are employed in small amounts with suitable baits, high kills of both rats and mice have been observed within a few days.
Since its commercial introduction in 1950, warfarin has been prepared and employed in a variety of compositions and forms. U.S. Pat. No. 2,783,177 describes the preparation of the sodium salt of warfarin which may be employed as a water bait. Aqueous solutions of the material may be coated on sand which may subsequently be placed in water, whereby the water soluble warfarin compound dissolves, the sand merely serving as a "carrier" for the rodenticide. U.S. Pat. No. 3,105,321, describes an anti-mouse board which appeals to the gnawing and destructive tendencies of a mouse, which unlike the rat, tends to chew or pick at their food, eating only small amounts at a particular time, but feeding often.
Warfarin, which at the time of its introduction was thought to be the most efficacious rodenticide, has in recent years proved to be less effective. Apparently, rodents have developed a resistance to the anticoagulent effect of warfarin. The exact mechanism for this resistance is not known,however, it is believed by some that if the organism can synthesize enough vitamin K, an anti-hemorrhagic compound, then the effects of anticoagulants are greatly reduced. Considering the competing effects, one approach to overcoming the resistance of organisms to anticoagulants has taken the form of combining the anticoagulant with sulfa drugs and/or an antibiotic. The belief was that such substances would reduce or eliminate intestinal flora which are responsible for synthesis of vitamin K. It was thought that this combination of components would potentiate or magnify the activity of the anticoagulent compound; however, such approaches have had only limited success in combating the resistance developed by rodents to anticoagulants. Thus, until the instant invention was developed, what once appeared to be the final solution to the rodent problem, seemed only to present a temporary holding action.